1. Field of the Invention
The invention relates to an insertion-type connector and in particular to a co-axial radio-frequency insertion-type connector, and to an insertion-type connection formed by an insertion-type connector of this kind and a mating insertion-type connector complementary thereto.
2. Description of Related Art
In many known radio-frequency insertion-type connections, the making of contact between at least the outer conductors of the two insertion-type connectors takes place (among other ways) axially, i.e. contact-making faces at the ends of the outer conductors butt against one another when the insertion-type connections are in the plugged together state. To achieve transmission of radio-frequency signals through the insertion-type connections which is as free as possible of intermodulation and reflection, a comparatively high contact-making pressure is usually required. In many insertion-type connections this is produced by means of a union nut which is arranged to be rotatable on the shell of one of the insertion-type connectors, this shell often being formed by the outer conductor, and which has an inside thread which can be screwed onto an outside thread on a shell of the other insertion-type connector, this shell often being formed by the outer conductor. The screwing-up of the union nut moves the two insertion-type connectors relative to one another in the direction defined by their longitudinal axes (which corresponds to the direction of insertion) and thereby produces the axial contact-making pressure. The union nut then also ensures that the insertion-type connectors are held fixed durably, but in such a way as to be releasable again, when the radio-frequency insertion-type connection is in the plugged together state. A radio-frequency insertion-type connection of this kind is known from, for example, DE 43 00 243 C1.
In screwed connections in general, self-loosening may occur due to relaxation but the connections are usually secured against this. There are a large number of securing members available for this purpose such for example as disc springs, shake proof washers and spring washers.
There are various reasons why securing members of this kind have not so far been used for the securing of the screwed joint in a screwed connection fixed with a union nut. One reason is the space which is not usually available for incorporating a securing member of this kind. Another reason is the restricting of the convenience of use when, once the insertion-type connection has been plugged together, it has to be checked that a securing member is present and is correctly seated. And finally, the securing member must not cause any adverse change in the electrical transmission characteristics, as the securing member would in radio-frequency insertion-type connections if it were arranged between the axial contact-making faces.
In known radio-frequency insertion-type connections, securing against self-loosening is therefore usually accomplished by tightening the union nut to a comparatively high tightening torque which will compensate for the relaxation which can be expected of the screwed connection. This however makes it difficult for the insertion-type connection to be plugged together and may also result in damage to the insertion-type connectors involved.